Electric railroad-signal



G. D TISDALE. 2 Electric Railroad Signal.

No; 229,285. Patenfed June 29,1880.

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UNITED STATES PATENT OFFIQE.

CHARLES D. TISDALE, OF BOSTON, MASSACHUSETTS.

ELECTRIC RAI LROAD-SIGNAL.

SPECIFICATION forming part of Letters Patent No. 229,285, dated June 29,1880.

Application filed September 6, 1879.

To all whom it may concern:

Be it known that I, CHARLES D. TISDALE, of Boston, of the county ofSuffolk and State of Massachusetts, have invented a new and usefulImprovement in Electric Signal Apparatus for Railways and I do herebydeclare the same to be described in the following specification andrepresented in the accompanying drawings, of which Figure 1 is a topview, Fig. 2 a front elevation, and Figs. 3 and 4 opposite end views, ofit. Figs. 5 and 6 are opposite side elevations of. the intermediate orswitch post with the devices applied thereto.

The nature of my invention is set forth in the claim or claimshereinafter presented.

This signal apparatus is to give notice to a car or train, whenapproaching either of the two next adjacent signal-posts, whether thesection of track between them is clear of any train or car, or, whenthere is a switch in the section, whether such switch is closed or in acorrect position for the train or car to pass throughout the section.

In this apparatus, when the signals are down, so as to cover theiropenings of the signal-post heads, a car or train is to be supposed tobe on the section, or that the switch is open or not inalignment withthe track-rails, in which case it will not be safe for another orapproaching car or train to pass upon and through the section.

The two signal-posts are generally to be placed a mile, or about thatdistance, apart, the switch and its post being intermediate of orbetween them, in manner substantially as represented.

In the drawings, A and B denote the two signal-posts, and G theintermediate or switch post, all of which are arranged aside of andclose to a railway-track, D D, and a switch, E E, thereof.

Each of the signal-posts A B has a circular box-head, a, provided at itscentral part with a circular opening, I), and within each head is alever-signal, F, which is pivoted to the head, so as when down to coverthe opening 1) thereof.

Arranged below each signal is an armature or box, G, which, near one endof it, is pivoted to the head a, it being disposed over anelectro-magnet, H, and connected near its free end by a rod, 0, with theshorter arm of the signal-lever.

Near each post four wires proceed from the track, those of the post Abeing marked (1 c fg and those of the post B being marked l i k b. Eachwire leads from a separate rail of the next line of rails of the track,these rails being in Fig. 1 marked m 10,010 for post A and q r s t forpost B. The rail to which each wire is attached is to be electricallyinsulated from those next it, though there may be between any two nextadjacent of such rails one or more line-rails, as shown in the drawingsat u.

The galvanic battery is represented at K. From one of its poles twowires, to b, are led, while one wire, e, is led from the other pole. Thewire a leads to and around the first magnet, H, and thence to the heelof a circuitcloser or metallic spring, L, arranged as shown, such springbeing bent inward near its free end, in order that when the armature Gnear it is depressed such armature, or a bent-wire projection, (1,extending down from it, may be carried in contact with the spring L andcause it to be moved into contact with a turned-in portion of thecircuit-wire c. The said wire 0' is continued from directly under thespring L to and down the intermediate post, 0, to the metallic pivot yof a metallic vibratory arm, M, such arm being arranged against onesideof the post and pivoted thereto.

From the arm M a rod, f, extends nearly to the switch-rail E when theswitch is closed. The rod should not touch the switch, or should beinsulated from it, when the switch is closed in the main track. Theturnout-track is not shown in the drawings. It is to be supposed to bearranged with the switch and main track in the usual manner, the switchbeing open when in alignment with the turnout-track or out of alignmentwith the main track.

A spring, g, suitably applied to a stationary stud, h, and wound aroundthe rod and attached to the arm M, serves to move or draw back the saidarm M and the rod f while the switch is being moved into alignment withthe maintrack.

The arm M is to operate with two metallic studs, t" k, inserted in thepost G.' From the stud i the circuit-wire 6, broken or interruptedbetween the pivot of the arm M and the stud '5', continues from the saidstud up the opposite side of the post C, and thence to and about themagnet H of the post B, and thence to the other pole of the battery.

About the stud It a wire, l, is carried in its passage from the wire aat the magnet oi" the post A, such wire passing up to the top of thepost 0, and going from thence to and down the post B, and thence to therail t.

The wire 6, attached to the rail 8, is led to the post B, thence up thesaid post to the circuit-wire c.

From the first-mentioned pole of the battery the short-circuit wire 1),before referred to, is led to the rail q.

The wire 76 from the rail 0" leads toward and up the post B, and iscoupled with the circuitwire 0 near the magnet of the post B, as shown.

The wire g, leading from the rail P, couples with the shortcircuit wireI). The wire f, leading from the rail 0, goes to and up the post A andcouples with the main-circuit wire 6. So the wire 0, leading from therail it, goes to and up the post A and couples with the circuit-wire 0directly in front of the said post.

The wire 61 from the rail m leads to and up the post A and couples withthe magnet-wire l near where such wire is coupled with the wire a.

From the above it will be seen that the operative electric circuits areas follows-that is to say: First, the main circuit, or that between thetwo posts A B, starts from one pole of the battery by the wire a andcontinues through the same to and around the magnet of the post A, andfrom thence to the heel of the spring L, thence through said spring tothe turned-in portion of the wire 0, thence through said wire to andaround the magnet of the post B, and from thence to the other pole ofthe battery.

One short circuit, for breaking the main circuit by means of a car, whengoing from the postA toward the post B, commences with the rail 10,passes through the wire g to the wire I), thence to one pole of thebattery, thence from the other pole of said battery, through the wire 6,to and through the wire f and to the rail 0, it being completed when thewheels of the car are on the rails o and 19.

After the main circuit has been broken it will be closed, when thewheels of the car, in going from the post A to the post B, may reach andrest upon the railss t, the circuit then through such rails being asfollows-that is to say, by the wire I to the wire a near the magnet ofthe post A, thence around said magnet to one pole of the battery, thencefrom the other pole of said battery through the wire 0, thence to andaround the magnet of the post B, thence through the wire 'i to the rail8, thence through the wheels of the car to the rail 25.

When the train is going from the post B toward the post A the shortbreaking circuit is made or closed by the wheels resting upon the railsq and a", in which case the current is from the rail q, through the wireI), to one pole of the battery, thence from the other pole to andthrough the wire 6, the wire 7c, and thence through the latter to therail 1", thence through the wheels of the car to the rail q.

On the car passing upon the rails m and n the main circuit will beclosed. Starting from therail m, said circuitis through the wired toitscoupling with the wire I, thence through said wire l to the wire a,thence through said wire to around the magnet of post A, thence down thewire a to the pole of the battery. From the other pole it is through thewire 0 to and around the magnet of the post B, and from thence,loy thewire a, to and through the wire 6 to the rail n, and through the wheelsto the rail m. y

The operation of the apparatus as above described may be thus explained.

We will suppose a train or car to be approachin g the post A and to runtherefrom to the post B, and that the track between the said posts isclear and the switch closed the circuit of both magnets will be closed,and the target or signal'levers will be up so as to uncover the holes ofthe post-heads. Should there be a car or train on the section or theswitch be open the targets will be down.

On the car or train entering the section and two wheels of the engine orcar coming at once into contact with the two rails 0 p, the main circuitwill be broken and the magnets will cease to hold down the armaturesconsequently both targets will drop. On the car or engine passing uponthe two rails s and t the main circuit will be closed and the targets beraised up. So on the car or train entering the section and passingthrough it the opposite way, when the wheels come into contact with therails 'r and q, the main circuit will be broken and the targets willfall, such main circuit being closed when the wheels may be on the railsm and n, in which case the targets will rise. The wheels that are incontact with the two insulated rails are to be supposed to beelectrically connected-that is, so that the electric current can passfrom one to the other of them.

We will now suppose the switch to be moved for the purpose of opening itinto alignment with the turnout-track. On the arm M passing off the studi the main circuit would be broken and the targets would fall were itnot that the arm M is carried in contact with the stud h before such armmay leave the stud '2". The arm M, continuing to move, passes off thestud k on the switch coming into alignment with the turnout, andconsequently the circuit becomes broken and the targets fall and thebent wire dbecomes raised off the spring L.v Were it not for the stud kand the wire l, leading to the circuit-wire at the magnet of the post A,the main circuit could not be closed when the arm M might reach the studi, for the wire d would be off the spring L, whereby there would be abreak in the circuit. As soon, during the returnmovementof the switch,

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as the arm 'M is carried in contact with the stud k the circuit will beclosed and the targets will be raised, the said break in the circuitbeing then closed. On the arm M passin g to the stud i the circuit willbe kept closed when the arm leaves the stud k.

The electric signal apparatus described in the specification of LettersPatent No. 218,693, dated August 19, 1879, granted to me, was speciallyintended for a double-track railway, where the trains going in -onedirection always run on one track, and when going the opposite way theyrun on the other track. The circuit in such case had to be broken on atrain entering the section of track and closed on passing therefrom.

My present signal apparatus is for a singletrack railway on which thetrains run-each way, or on which two trains may approach each other onthe same track.

To adapt the electric signal apparatus to the sin gletrack railway itWill be seen that at or near each end of the section provision is madeboth for closing and breaking the circuit, and that this is accomplishedin part by means of certain of the rails of the track and by the wheelsof a truck or carriage, all as described.

In case of there. being no switch in the section the circuit-wire e isto continue unbroken oruninterrupted from one post, A, to the other, 13,there being under such circumstances no intermediate post, 0.

Having thus described my invention, what I claim as such is as follows:

1. The single-track electric signal apparatus or combination,substantially as described, consisting of the four sets of insulatedrails m n, o 19, gr, and s t, the battery K, continuouscircuit wire a,magnets H, circuit closer or spring L, wires 01, 6,f, g, a, b, k, i, andl, and the armatures G and signal-levers F, all adapted to operateessentially as set forth, and for use on a track without a switch.

2. The combined single-track and switchsignal apparatus or combinationof the studs i k, Vibratory arm M, rod f, and spring g, adapted to thepost 0, and the switch, as described, with the four sets of insulatedrails m n, 0 p, q r, and s t, the battery K, the circuitwires 6, magnetsH, circuit-closer or spring L, wires 02, e,f, g, a, b, k, i, and l, andthe armatures G and signal-levers F, all being applied and to operatesubstantially as set forth.

CHARLES D. TISDALE.

Witnesses:

S. N. PIPER, W. W. LUNT.

